Polycarbonates are widely used engineering thermoplastics because they feature an attractive set of physical and mechanical properties. A disadvantage is, however, associated with their processing in that they have poor release properties. In an injection molding application, this disadvantage translates to relatively long cycle times. Shorter cycle times have been attained by injection molding at higher temperatures and by using mold release agents. Improving the release properties of polycarbonate compositions by the incorporation of long chain aliphatic carboxylic acid esters of monohydric and trihydric alcohols has been reported in German published Specifications DOS 2,064,095 and 2,220,185. U.S. Pat. No. 4,007,150 disclosed the use of perfluoroalkane sulfonic acid amides and/or cyclic ammonium salts of such acids as mold release agents. Relevant technology has been disclosed in U.S. Pat. No. 3,784,595 which refers to polycarbonate molding compositions having improved release properties containing an ester of trihydric alcohol and a C.sub.10-22 -saturated aliphatic carboxylic acid. These esters are said to be effective mold release agents, without at the same time causing a measurable quality lowering degradation of the polycarbonate. Also relevant in this context is U.S. Pat. No. 3,836,499 which disclosed esters of monovalent C.sub.10-35 -alcohols and aliphatic saturated C.sub.8-25 -monocarboxylic acids. U.S. Pat. Nos. 4,131,575 and 4,143,024 disclosed relevant mold release technology entailing polycarbonate compositions and esters of saturated aliphatic carboxylic acid and respectively, 4-hydric to 6-hydric alcohols, and aromatic hydroxy compounds with from 1 to 6 OH groups. Also relevant is U.S. Pat. No. 4,446,268 which disclosed an asymmetric carboxylic acid ester having a long chain alcohol component said to have effective mold releasing properties in several thermoplastic resins, including polycarbonates.
Hydrogenated castor oil, has been reported to serve as an internal lubricant and to improve the heat stability of PVC compounds; it is also reported to be a processing aid/flow promoter for both polyethylene and polypropylene.